TL:DR How can I make a bridge permanent (survive reboot) without adding a network device to the bridge config in /etc/network/interfaces?
Hi, I just started playing around with lxc on ubuntu 14.04.
The setup I would like to accomplish is, one container with haproxy, one with nginx.
I will dnat external requests via iptables to the haproxy and from there to nginx.
All of the containers will be in their own subnet. Routing/packetfiltering between the containers will be done by the host.
I've managed half of the setup so far.
I created two bridges with brctl and added IPs to the bridges.
br-haproxy: 10.100.0.1/24 br-nginx: 10.100.3.1/24
I then added the respective bridge to the corresponding container via the lxc config.
nginx got br-nginx haproxy got br-haproxy
Then I configured IP addresses in the containers.
haproxy: 10.100.0.10/24 GW 10.100.0.1 nginx: 10.100.3.10/24 GW 10.100.3.1
I was now able to ping between the two containers and so on. I now denied access by setting the forward policy from iptables to deny. I was now able to control traffic between the two containers via iptables.
Ok so far so good. What I now want to achieve is, make the bridges permanent. I added the bridgeconfig to /etc/network/interfaces but since I don't have a network device to add to the bridge I left this part out.
When I now try to initiate the bridge I get an error stating that the device e.g. br-haproxy couldn't be found.
I figured out, that the problem is the missing device in the bridge config. When I add eth0 from the host to the bridge config I can initiate the bridge and it comes up quite nice. But that's not what I need.
LXC dynamically creates and adds the interfaces from the container on startup of the container to the corresponding bridge.
So here comes my question. How can I make the bridges permanent without adding a network device to the bridge on boot?
Hope I made it somewhow clear what the problem is. :-)
Thanks in advance.